Research and innovation in central Europe is held back by the emigration of scientists and engineers. Rather than framing policies around encouraging their permanent return, the EU should help universities establish brain networks, in which modern communications enable scientists in the diaspora to contribute to research at home.

President Trump’s move to impose tariffs on steel and aluminum imports has fired the starting gun on an innovation war, in which the US aims to protect advanced technologies from Chinese incursions. Europe risks being caught in the cross fire